The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
There is known, from the prior art, a metal brazing tooling using the principle of thermal expansion, which cannot be applied in this instance, because of the high thermal expansion coefficient of Inconel 625.
It is also known, from the prior art, a brazing tooling using gas pressurization. Such a device comprises a central cylindrical drum constituting the gas chamber, contained in a counter-shape on which is fixed by screwing a sealing device constituted by upper and lower flanges. The pressure is applied on a cylindrical inner skin, thereby pressing said skin against a honeycomb structure, and then the set constituted by the inner skin and by the honeycomb structure against an outer skin. Afterwards, the inner skin/honeycomb structure/outer skin cylindrical set, is deformed under the effect of pressure until meeting the counter-shape whose inner surface adopts the desired final shape.
Such devices present drawbacks, in particular in that the use of a metal brazing tooling is expensive, not only per se, but also in terms of maintenance, and implies furthermore an additional cost of the thermal cycle related to the inertia of the tooling; the use of a brazing tooling by gas pressure presents in particular the drawback of implying an additional cost for achieving gas tightness, as well as technical difficulties such as mastering the parameters of pressure, time and temperature in order to avoid crushing of the honeycomb and to improve the marking phenomenon of the honeycomb (telegraphing) on the skin.